Father of the Bride (walking down the aisle):
Long before women's rights and the 1920's, brides were literally handed over by their fathers. Women (often at birth) were bound to one man and later in life were 'given away.'
Seating for Families:
A marriage in ancient times would be set to bring order and peace with warring clans (aka, intrusive in laws). To prevent the claws from comin' out during the nuptials the families were seated on opposite sides of the church.
Bride Standing on the Left:
According to ancient bridal books (you caught me, there's no such thing) it was common for the bride to be kidnapped and held for ransom. To protect the blushing 'booty' the bride was placed on the groom's left in order to leave his sword-hand free in case he had to defend her. So stinkin' noble, right?
Meaning of Wedding Bands:
The Greeks believed that the forth finger on the left hand has a vein that leads directly to the heart. The circle shape represents eternal love and adoration.
Kissing the Bride:
In the Roman Empire, a kiss between a couple symbolized a legal bond ("Sealed with a kiss.") They believed that a kiss was a way to join each others souls. (And, a side note...please don't play tonsil hockey during your wedding. Grandma didn't sign up for a preview of the honeymoon.)
Now, although your beau may not be equipped with sword and shield on your big day, these traditions define what makes weddings so special today. So as you walk down the aisle to stand on the left, put that pretty round ring on your forth finger and seal it all with a smooch.